glibc/sysdeps/s390/multiarch/wmemcmp-vx.S

150 lines
3.8 KiB
ArmAsm

/* Vector Optimized 32/64 bit S/390 version of wmemcmp.
Copyright (C) 2015-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
# include "sysdep.h"
# include "asm-syntax.h"
.text
/* int wmemcmp (const wchar_t *s1, const wchar_t *s2, size_t n)
Compare at most n characters of two wchar_t-arrays.
Register usage:
-r0=tmp
-r1=number of blocks
-r2=s1
-r3=s2
-r4=n
-r5=current_len
-v16=part of s1
-v17=part of s2
-v18=index of unequal
*/
ENTRY(__wmemcmp_vx)
.machine "z13"
.machinemode "zarch_nohighgprs"
# if !defined __s390x__
llgfr %r4,%r4
# endif /* !defined __s390x__ */
clgije %r4,0,.Lend_equal /* Nothing to do if n == 0. */
/* Check range of maxlen and convert to byte-count. */
# ifdef __s390x__
tmhh %r4,49152 /* Test bit 0 or 1 of maxlen. */
lghi %r1,-4 /* Max byte-count is 18446744073709551612. */
# else
tmlh %r4,49152 /* Test bit 0 or 1 of maxlen. */
llilf %r1,4294967292 /* Max byte-count is 4294967292. */
# endif /* !__s390x__ */
sllg %r4,%r4,2 /* Convert character-count to byte-count. */
locgrne %r4,%r1 /* Use max byte-count, if bit 0/1 was one. */
lghi %r5,0 /* current_len = 0. */
clgijh %r4,16,.Lgt16
.Lremaining:
aghi %r4,-1 /* vstl needs highest index. */
vll %v16,%r4,0(%r2)
vll %v17,%r4,0(%r3)
vfenef %v18,%v16,%v17 /* Compare not equal. */
vlgvb %r1,%v18,7 /* Load unequal index or 16 if not found. */
clrj %r1,%r4,12,.Lfound2 /* r1 <= r4 -> unequal within loaded
bytes. */
.Lend_equal:
lghi %r2,0
br %r14
.Lfound:
/* vfenezf found an unequal element or zero.
This instruction compares unsigned words, but wchar_t is signed.
Thus we have to compare the found element again. */
vlgvb %r1,%v18,7 /* Extract not equal byte-index. */
.Lfound2:
srl %r1,2 /* And convert it to character-index. */
vlgvf %r0,%v16,0(%r1) /* Load character-values. */
vlgvf %r1,%v17,0(%r1)
cr %r0,%r1
je .Lend_equal
lghi %r2,1
lghi %r1,-1
locgrl %r2,%r1
br %r14
.Lgt16:
clgijh %r4,64,.Lpreloop64
.Lpreloop16:
srlg %r1,%r4,4 /* Split into 16byte blocks */
.Lloop16:
vl %v16,0(%r5,%r2)
vl %v17,0(%r5,%r3)
aghi %r5,16
vfenefs %v18,%v16,%v17 /* Compare not equal. */
jno .Lfound
brctg %r1,.Lloop16 /* Loop until all blocks are processed. */
llgfr %r4,%r4
nilf %r4,15 /* Get remaining bytes */
locgre %r2,%r4
ber %r14
la %r2,0(%r5,%r2)
la %r3,0(%r5,%r3)
j .Lremaining
.Lpreloop64:
srlg %r1,%r4,6 /* Split into 64byte blocks */
.Lloop64:
vl %v16,0(%r5,%r2)
vl %v17,0(%r5,%r3)
vfenefs %v18,%v16,%v17 /* Compare not equal. */
jno .Lfound
vl %v16,16(%r5,%r2)
vl %v17,16(%r5,%r3)
vfenefs %v18,%v16,%v17
jno .Lfound
vl %v16,32(%r5,%r2)
vl %v17,32(%r5,%r3)
vfenefs %v18,%v16,%v17
jno .Lfound
vl %v16,48(%r5,%r2)
vl %v17,48(%r5,%r3)
aghi %r5,64
vfenefs %v18,%v16,%v17
jno .Lfound
brctg %r1,.Lloop64 /* Loop until all blocks are processed. */
llgfr %r4,%r4
nilf %r4,63 /* Get remaining bytes */
locgre %r2,%r4
ber %r14
clgijh %r4,16,.Lpreloop16
la %r2,0(%r5,%r2)
la %r3,0(%r5,%r3)
j .Lremaining
END(__wmemcmp_vx)
#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */